Hi, not sure where you are but i'm surrounded by these [in nz], must be an illness, RH drive by the way but anyway hope this help from my personal experience & had to more or less work it out for myself by following airways through. [Cold] Fast idle seems to be controlled mostly if not totally by a thermostat controlled airway to the inlet [somehow]. LH side & has two small screws holding a flat plate over access to a plastic tapered item that can be screwed clockwise to set it nearer the thermostat controlled tapered thingy that is pushed up until it eventually cuts off the air which then is totally controlled by the idle speed air adjustment. Just altered one of mine & rotated it a turn which was enough but may need more. My other car which has the 2.5 G25a motor [identical to the G20a] I adjusted years ago but is creeping back up so possibly that little thermostat is faulty & not lifting it soon enough or the threaded plastic thing has wound back a bit as has nothing stops it except thread tightness as such. Has a two opposing slots for two screwdrivers & drag it around or what I did was use my expanding circlip pliers & turn it. Good luck.
Ps, Tried to attach a photo from the net but won't work so will give the address. Flat plate lines up with the letter F above in one of the bright lower photos & is just below the accelerator cable--[you'll see it], nothing 'jumps out' when you take that plate off, just covers the access to the adjustment ring. Also from the pic you can imagine a small thermostat to lift the shut of plastic taper thing in the lower section. OK, ebay auction 350690698569. Thanks. M.
Tuesday, January 15th, 2013 AT 5:07 AM